Art of distillation



June 24, 1930. =H, v WELCH ART oF DISTILLAT'ION 2 Sheets-Sheet l qled July 22, 1925 f *E e 2 WW v/ W 2 Y. o M B a w 02 62 E W .4 'D Wizz 2 0 w June 24, '1930. IH. v. WELCH 1,768,179

ART OF DISTILLATION ATTORNEY i Patented June 24, 191i() stages but the liquid condensing Ato tion thereof, and such .fying column, i ration therefrom of constituents which are'.

vvUnirse ASTAT-es PATENT orale HARRY v. WELCH, 0F LOS ANGELES, UALIFOENI, ASSIGNOR TQ INTERNATIONAL PRECIPITATION CALIFORNIA Application led July 22,

is customary to subject the hydrocarbon oil, either in the form of crude petroleum or a partially refined petroleum product, or other liquid to be distilled, to the action of heat to volatilize some of the constituents thereof, then to remove the liquid and to subject the same to cooling, preferably in two or more stages so as to separate or condense therefrom conden- Ysates of different volatility. -Such condensation may be either of the type known as rectiying condensation in which the vapors are subjected to a reduction' of temperature by out at each stage is not immediately separated but is subjected to redistillation under the inuence of heat received in part from the condensation of higher .boiling fractions in the precedingstage, thus providing a shar er separation ot' the various constituents o the vapor, or it may be of the type known as simple condensation, in which the vapors are subjected to cooling resulting in condensation of a porportion is removed and the vapors then subjected to further cooling to separate another portion,.etc'.. rlhe former type of condensation is usually carried out in what are known as rectifying columns or rectifying condensers, through which the vapors ypass upwardly and are continually reduced in temperature, while thev condensate formed as the gases are progressively cooled is collected at various levels and is subjected ,to the heat of the gases which reach such levels and to the latent heatreleased by condensation ofv higher bolling fractions in the lower sections of the rectisoas to'cause a further evapovolatile at that temperature and cause the ultimate reduction 'of eachof the bodies of liquid so collected to a single const1tuent o f nthe 'distillation processes now employed for this purpose 1t such resulting vapoie froml vobjectionable nature,

COMPANY, or Los ANGELES, CALIFORNIA, A oonPonATIoN or" ART OF DISTILLATION' 1925. serial no. 45,197.

the vapors or to constituents having approxboiling points.

`trainment of condensed particles in the form of a mist are of particular importance in the case of rectifying columns, since reater pains are taken in'that-case to -so deslgn the apparatus as to obtain a very sharp separation of the constituents ofthe vapor, and the efforts thus expended are often' rendered entirely useless due to the entrainment or carrying over of condensed particles of liquid from one stage of the rectifying column to a higher stage. rlhe disadvantages of such enf trainment are also particularly noticeable and objectionable in cases in whichthe vapors entering the condenser contain constituents having vva higher boiling point than the product to be obtained and of a lparticularly such as tar or tarry or asphaltic material in oils, which condenses entrained as a cloud with and contaminates the lighter constituents collected later on. An important object of my invention is to prevent contamination of the more volatile or lighter constituents by the lessvolatile objectionable constituents. Furthermore, contamination may be caused in some cases, by mechanical entrainthe case of hydrocarbon out first and which, if

y invention consists in the use of electrior mist, becomes mixed.

of condensation the condenl vment of unvaporized liquid particles'from l cal precipitation methods-for the'separation Y within, before, or between successive stages of condensation of any condensate or entrained liquid formed or present as a mist orl cloud within, before or between such stages, thus rendering the separation much sharper and more positive than has heretofore been possible. The invention is particularly applicable and is of the greatest advantage in connection with rectifying condensation but may also be applied in connection with simple condensation, but in either case it brings about the removal from vthe vapor within each stage, or between each stage and the next succeeding one, of any condensate Aformed in that stage, and thus prevents the contamination of the more volatile constituents by the presence of less volatile constituents which would otherwise be carried over as above described, and when practiced before the iirst stage of condensation it also eliminates the contamination of the product by mechanically entrained unvolatilized impurities or by high boiling constituents which condense before actually reaching the condenser.

A further advantage which results particularly from the provision of an electrical precipitating o eration during at least a portion of each coo ing and condensing operation is that such electrical precipitating operation creates or causes a migration of the gas itself in a direction from the discharge electrode toward the collecting electrode, such phenomenon being termed electric wind. This causes'the gas to be kept continually in cirp culation, and increases the uniformity with' which Vdilferent arts of the gas are brought into contact lwit the cooling surfaces and thus still further promotes the sharpness of separation.

The accompanying drawings illustrate embodiments of iny invention and referring thereto:

Fig. 1 is a diagrammatic view of a pipe still and a rectifying condenser provided with.

means for electrical precipitation#according to my invention.

Fig. 2 is a vertical section of the rectifying condenser shown in Fig. l. i

Fig. 3 is a horizontal section on line 3-3 in Fig. 2. l f

Figs. 4, 5, 6, 7, and 8 are partial vertical sections of modified forms of condensers.

Y Fig. 9 is a horizontal section on line 9-9 in Fig. 8.

Fig. 10 is a diagrammatic view of a steam still provided with condensing means accordving to my invention. v

Fig. 11 is a dia rammatic view of another modified form o condensing means as applied in connection with a-steam still.

In. Fig. 1 l have shown at l a pipe still type. uch still is here shown as comprising a housing 2 of brick or other refractory material and constitutin'g acombustion chamber or lire box 3, 'heating orpipe chamber 4,V and a Hue 5. Burner means 6 are provided in the combusheader to the lower portion of rectifying column l3.`

Said rectifying column comprises, as more clearly shown in Figs. 2 and 3, an outer cylindrical'shell or casing 14 and a plurality of alternating trays 'or pans 15 and 16 within said casing, the trays 15 being mounted upon the cylindrical casing 14 and having an upturned flange or fining a central opening 18, and each of the pans 16 beingmounted upon a central rod or other supporting means 2O and having an upturned flange or lip 21 at its outer edge, thus providing an annular opening-22 between said iiange and the outer casing. The vapor entering through pipe 12' at the bottom of the column is thus caused to follow a tartuous path upwardly therethrough due to the alternate arrangement of the'trays 15 and 16, and suitable exit means such as pipe 24 are connected to the upper end of the column to carry away therefromthe uncondensed por'' tions of the vapor. Suitable drain means such as pipe 25 may be provided at the bottom of the column for continually or intermittently drawing olf unvolatilized liquid carried over through vapor line l2, such unvaporized liquid being discharged or being advantageously returned to the supply line 11 leading to the still as is customary in such processes. Suite lip 17 surrounding and deable drain means are'also provided for each.v

of the trays 15, such drain means comprising for example pipes 26 provided with valves 27.

"My invention may comprise in connection' trays 16 carried thereby from the outer casing 14 and the trays 15, for example by means of an insulating plug or bushing 28 at vthe upper end of the casing1 and adapted to support saidl supporting rod 20 in central position within the casing as well as to electricallyl insulate the same therefrom. The supporting rod 2O is provided with a portion 29 projecting through the insulating means 28 and connected to suitable means for supplying high tension electrical current thereto, for example wire 30. rilhe cylindrical casing 14 is' grounded in any suitable mannerv either by course be omitted, and

connection of a grounded wire thereto or sim ply by grounding a metallic portion of such casin las indicated at 31. Any suitable means may e' used for supplying the necessary poi other side of which sourceis grounded. Said source of high tension current may be adapted to maintain any desired potential between the discharge system and the collecting system, for exam le 15,000 to 100,000 volts. have shown in ig. 1, for example, the wire 30 connected to a mechanical rectifier 30, having a ground connection 30" and connections to the secondary winding of a ste -up transformer 30c whose primary winding is connected to any suitable alternating current supply circuit. In case alternating current discharge is to be used, the rectifier would of wire connected directly to I/one side of the transformer secondary, the other side of which would be grounded.

I In the form of the invention shown in Fig. Y

2 the primary cooling of the vapors is accomplished wholly by the cooling or the outside walls 14 by the surrounding air, although as will be hereinafter described loca condensa-l tion may occur in the vapors striking the bottom of each of the pans or trays 15 and 16 due-to the fact that the condensate collected in such pans is in each case of somewhat lower temperature than such vapors. As indicated in Fig. 4; however additional cooiing means may be provided such as pipes or coils.

35 located beneath each of the pans or trays 15 and connected by means of inlet pipes 36 and outlet pipes not shown for circulation of cooling water therethrough. 0r as shown in Fig. 5, the walls 14 of the con enser may be cooled by means of a water jacket 37 surrounding the outer casing and provided with means for circulating cooling water or, if desired, other cooling medium therethrough.

Modilications may also be made in the shape, construction, or arrangement of the trays 1 5 and 16 of the rectifying column. For example as shown in Fig. d the inner trays 16 may be provided with holes or per- I forations 38 in thel bottom so that the liquid condensing therein may fall through such holes onto the tray 15 beneath instead of belng required to pass over the edges of the such discs.

flanges 21 as in the form yshown in Fig. 2. Or as shown in Fig. 5 the danges 21 may be omit ted and the-trays 16 may consist simply of flat discs, the liquid condensing thereon in this case sim ly passing over the edges 39 of In some cases however it may be preferable to provide for 'collection or a body either alternating or direct, butsuch as water Aof liquid of' considerable depth in the-trays,- 16 as is provided for in the form shown `1n Fig. 2, but at the same time prevent the liquid in dropping from such trays onto the trays 15'from passing over the edge portions of the trays 16 and. anges 21 from which the electrical discharge takes place.I For example, as shown inv Fig. 6 trays 16 may be provided with portions 40 projecting outwardly beyond the upturned flanges 21 and having perforations or holes 41 therein for passage of liquid. In this case the liquid collects and. runs overthe top of flan e and through'holes 4.1, leavin the outer edges of portions40 `free from Iiquid so yas to facilitate electrical discharge therefrom;

In other cases I may prefer to form the Lso inner trays 16 as Hat dlscs, and the outer trays 15 as relatively narrow annular troughs, whose upturned anges 17 are close to the cylindrical casing 14 and provide a large central opening or passage 18 therethrough,` as 'shown in Fig. 7. A somewhat similar construction is shown in Figs. 8 and 9, in which the supporting means 20 consists however of a cylindrical tube or-casing instead of a rod, the trays 16 consisting in this case of horizontal ribs extending around said inner casing 20 and projecting therefrom.' Coolin means jacket 43 may be provided surrounding thev outer casing 14 and additional cooling mean also be provided within the innersupporting casing 20. In this case the supporting casing 20 and the ribs or trays 16 carried thereby are insulated from the outer casing so vas 'to constitute the high potentialdischarge s such as water jacket ed may-V v ice l In the operation of the apparatus above described, using an of the above types of construction of rectigfing column,the oil or other liquid tolbe subjected to distillation `is introduced to heating coils or pipes 8 through pipe 11 and is heated in said coils by the hot combustiongases from burner 6, said combustion gases passing from fire box 3 through heating v chamber dand thence out through flue 5. In

passing throuh the heating coils 8 the oil is raised to a sucient temperature to volatilize certain portions thereof and the vapors thus produced are carried together with unvola- -tilized oil through pipe 12 to the bottom of the condenser 13. The process ma be so car- Pied 'out that there will be a reduction of pressure at the point of entrance intothe lower end vof the lcondensercolumn, resulting inV further rae . volatilization' at this point', or there may be vsubstantially 'and 16 thereof while either'discharged or returned to supply pipe 11 with the incoming oil.

The hot vapors in passing upwardly l through the column are gradually reduced in temperature and lsuccessive portions thereof of increasing volatility are thus condensed to the form of a liquid. ln the usual type of recwalls 1l of the casing into til-ying column a portion o the liquid thus condensed at each level of the columnA falls `into the trays and 16 or other means pro-` vided or this purpose and drains down the the trays 15? and Y Vin these trays such liquid is subjected to a cer- Vci the vapors passingv tain amount of redistillation due to the heat the underside of the trays. A certain amount ci the more volatile portions of the condensed liquid 'are thus revolatilized and a more complete separation of the various constituents is obtained which is commonly known as rectiiication. rlhis revolatilization oi the more volatile constituents of the liquid condensed in eachtray also occurs inthe present instance. ln the ordinary type 'of rectifying column however a considerable portion oi the 'condensate formed at each level of the columnis produced in the form of a mist or cloud of particles orp such small size that they do not readily settle out and are thereby entrained with the vapors to a higher level in the column befoi'e separation. rThis results in the containination oithe lower boiling point constituents collected in the upper part of the column by considerable proportions cic higher boiling constituents which were actually condensed at a lower stage but were not separated until reaching a higher stage. .ein important cb- `ject of my invention is to'prevent such contamination and this is accomplished by setting up an electrical held at certain portions of the rectifying column, said electrical eld being sulhcient to eect agglomeration and side of the trays 15.

electrical precipitation of the condensate appearing in the form of a mist so that the vapors are continually maintained clean and free from entrained mist. The high tension system being energized as before described, an electrical field will he set up between the edges of the trays 16 orthe lip-turned rims 2l thereof and the outer wall 14 or the under t The electric discharge is in either case directed toward a cooling surface, that is, underside of one of the trays 5 permitted either toward wall i4 or thev i 15. The vapors I are thus subjected to the action et an electriinseam cal field in passing through the zone above each tray 15 to the zone above the next tray 15 so that any condensate formed in the zone above one of such trays even though it be formed as a mist or cloud is precipitated and collected in such tray, and onlyl the clean vapor free from suspended liquid particles is to pass into the zone above the next tray 15. A portion of the liquid is also collected in the trays 16 and subjected to redistillation, a portion of such collected liqf uid again passing 0E as vapor and the remaining portion continually discharging over the edges of such trays or through the holes in the bottoni thereof onto the trays 15 just below. A very sharp separation of the constituents or vapors is thus obtained and the liquid condensing and collecting in each tray 15 will have a very short boiling range and will be substantially reefrom contamination by constituents of higher boilin points. 'lhe c-ondensates thus collected in eac tray 15 may be drawn oil continually through the outlets 26 and may each be collected separately -or two or more adjacent outlets 26 may be connected together to provide for mixing of the condensates from several successive stages of the column.

ln addition to the precipitating action the electrical lield also creates an electric Wind, or a movement of the vapors themselves toward the collecting electrode surfaces and hence brings such vapors into more eective contact with the cooling surfaces and causes more uniform cooling thereof. Substantially all vapors passing through each cooling stage are therefore reduced to a very uniform 'temperature and the "sharpness of separation is still Jfurther increased.

The invention provides not only foutue immediate separation of condensed particles and consequent sharp separation, hut also for the removal of mechanically entraine liquid particles. lt will be seen that any unl vaporized liquid particles carried along as a spray or inist by the vapors from the bottoni of the column will he precipitated, together with the first portion of condensate, by the electrical iield above the lowermost tray 15, and will thus be prevented from reaching the upper sections of the column and contaminating the products. lf the liquid collected on lll) the lowermost tray or trays l5 is found to y be contaminated with precipitated entrained material it may be run back into the still eed pipe lor re-dstillation.

As shown in Fig. 1() my invention may also be applied in connection with simple condensation7 that is to say densation in which the condensed liquid is not subjected tov revolatilization but is removed rom the system directly after condensation. ln this case I have shown my invention as applied in connection with a type of still known asa steam still but it to a type ol' conwill vbe understood that the type of condensing apparatus shown in this form of the inf Fig. comprises a cylindrical shell or cas- 'troducing to the still 50 trolling the direction'of at the top ofthe condenser and ing 50 disposed horizontally and mounted upon a brick setting 51, and burner mea-ns 52 provided with fuel supply means 53 for applying heat to the underside of such casing. Oil supply means 11 are provided for inthe oil to be distilled, said'supply means having a downwardly extending `portion`54 extending beneath the normal level of the oil within the still, it

- y being understood that supply means 11 are also provided with suitable means for introducing the oil thereto at a suitable pressure. Steam supply means 55 are also provided for introducing steam to heat the oil inthe still 50 and said steam supply means are preferably provided with perforated coils 56 through which the steam issues into the oil and thus serves not only to aid in heating the oil but also to both agitate the same and. facilitate the liberation of volatile constituents therefrom. From the top of stillcasing 50 vapor line 12 leads to the condenser indicated at 58.

Said condenser 58 comprises a plurality of vertically extending ues, pipes or casin'gs 59 communicating at their upper ends with passage means 60 and at their lower ends with passage means 61, and suitable valve or damper means are provided for conpassage of the vapor through the respective vertical iues 59. Such damper means may comprise dampers 62 located between the adjacent upper passage means 60 and dampers 63 located between the adjacent lower passage means 61. Such dampers may be so operated as to cause the vapor to follow a zig-zag course through the condenser, rst passing u wardly and then downwardly, etc., throng the successive vertical iiluesl 59. As indicated however the position of the dempers 62 and 63 may be so regulated as to bring two or more of the adjacent lues 59 into parallel iow arrangement with one another at any desired polnt in the condenser so as to rovide for a slower How of the vapors at such point. The vertical flue/sor casings 59 are grounded as indicated at 64 and constitute collecting electrodes for the electrical precipitation system'. Suitable discharge electrode means are also provided comprising, for example discharge wlres 66 suspended vertically and centrally within the ilues 59 and, passing through suitable insulating and supportin means 67 icing connected for example by wire 68 to suitable means for supplying high tension electric l current thereto.v The discharge wires 66l may be 1provided with suitable weights 69 at their ower ends for tensioning the same and causing them to hang in properposition. Suitable liquid collecting or receivin means 70 are provided at the bottom of eac vertical flue 59 and outlet or drain means y71 are provided for carrying off the liquid collected in each of suchreceiving means.,

In the operation ofthis form of the-invention the oil to be distilled is supplied i through pipe 11 to still casing-50 and is heated therein by means of a frire maintained at burner means 52, and also by means of and coil 56. The volatilized portions of the oil, together with steam pass over through vapor pipe' 12 into condenser 58 and pass stages by means of the cooler air surround- Y ing the condenser tubes or if desired by means of suitable cooling coil or cooling jack- 'et means with which such condenser tubes may be provided, and portions of successively lower'boiling point are thus condensed in the successive pipes v59. The electrical iield maintained within each of said pipes 59,b means of the high tension discharge mem ers 66v serves to precipitate onto the walls of such pipes any liquid condensed therein in the form of a mist or. cloud and thus prevents entrainment of such condensed liquid into 4the next succeeding stage ofv the condenser. In this case also as well as in the form first described a much sharper separation of the constituents ing points is thus effected than would otherwise be possible, and particularly the contamination of the lower boiling portions by entrained vquantities of higher boiling constituents is prevented. The liquid condensed is precipitated in each of the vertical pipes 59 and collected in the respective receiving means 70 at the bottom thereof and may be drainedy olf either continually or intermittently through outlet means 71 to be collectedV for any suitable purpose. Some of the steam may condense to form water at of diiferrent boill.

certain stages of the condensation, and such continually maintained free fromsuspended liquid particles. lAny suitable meansmay lao It will be observed that inl this recipiy steam introduced through 4supply means 55 8o s be provided for coolin the successive stages ot the condenser, or t e samemaybe insulated at any desired part so as lto produce the desired rate of cooling. Any liquid particles mechanically ent-rained from the still by the steam and va ors will as before be precipitated in the denser, and it necessary the condensate from this stage may be redistilled, or treated in any suitable mannerfseparately from the later portions, `whichare tree Jrom such entrained impurities. lf desired, an electrical precipitating action may be provided in any case before the lirst stage of condensation, so as to of liquid carried over from the still without contamination. of any of the, condensate thereby. This may be accommplished, 'for example, by thoroughly insulating the lirst vertical pipe 59, so as to permit the same to act as an electrical precipitator without condensation therein, in which case only Inechanically entrained liquid particles will be condensed therein. v

The electrical precipitation need not in all cases be carried out simultaneously with the condensation as above described but may in.

some cases advantageously occur between successive stag-es of the cooling and ycondensation, for example, the apparatus shown 1n Fig. 11 is adapted to carry out my invention in this manner. The still shown in this figure is of the same type and comprises the same elements as that shown in Fig. 10. The vapor line 12 however leads first to one of a plurality of condensers comprising for eX- ample vertical tubes or casings 74, adapted to be air-cooled or provided with any suitable cooling means, and a plurality ot electrical preclpitation units comprising forexample vertical tubes or casings are connected in series and alternately with such condensers by means of connecting pipes 76 and 77.. With the arrangement shown the vapors pass downwardly through the condensing elements 74 and upwardly through the succeeding precipitating elements 75 but such direction of flow is not essential and in some cases l may prefer to reverse the connections so as to cause the vapors to ow upwardly through the condensing elements andv downwardly through the precipitating elelnents. The outer walls of the casings or precipitating elements 75 are grounded as indicated at 7 8 and suitable discharge electrode means are provided for such precipitating elements comprising `for example vertical wires 66 mounted and provided with means for energization thereof as above described in connection with Fig. 10i Suitable receiv-v ing means 79 and outlet means 80 .are provided at the bottom'of each of the precipitating ins tors from the condensers 7 4 tothe precipita- 7 frnay be'adapted as shown to carry any rst stage of the con-v provide for effective separationV units 75 and the connecting pipes 76 leady condensers and precipitators and are graduy ally reduced in temperature resulting lin the successive condensation in the respective con-v densers of portions of successively lower boiling points. A portion of the liquid lis condensed in each of the condensers and sepay rates out and drains to the bottom of the condenser and hence into receiving means 79 but a further portion of such condensed liquid` remains in the form of a cloud or mist and is not separated from the gas stream until it enters the succeeding 'electrical precipitator 7 5. Here such cloud or mist is precipitatedonto the walls of such precipitator and flows down and into the receiving means 79, so that the vapors passing from each of the precipitators into the succeeding condensers are clean and :tree from ent-rained liquid particles thus producing as before the desired sharpness ot separation of the vapors into constituents of dider'ent boiling points. When carrying out my invention in the last-described apparatus, it will be evident that if the walls of the preclpitation elements 75 are not protected against loss of heat, there will be some cooling of the vapors and consequently some condensation within such elements and simultaneously with the precipitating operation, and in some cases l may .prefer to operate in this manner or may even lll) described are particularly applicable in connection with distillation processes in which the vapors produced inthe still contain constituents' ot higher boiling point than the desired product, such as asphaltic constituents,

vor tar, or tarry materials either in the form of vapor or entrained ,liquid particles. In such cases'these tarry materials., 1t: present asa vapor condense first, and 1n any case are collected in the first the condensation, and by means'of'the elec-l trical precipitation occurring either simultaneously with the condensation or between successive stages thereof any portions of such tarry materials present or condensing in the form of a mist or cloud are precipitated out of the vapor stream and collected in or immediately following the stage in which they are condensed. In this. manner such tarry materials are prevented from being entrained and contaminating the lighter and more volatile constituents condensed in the later stages of the condensation.

While I have described my invention in connection with certain types of stills it will be apparent that it ma be applied with equal advantage to the rectifying or fractional condensation of vapors coming from any type of still. For example it may be used 1n the condensation of the-.vapors resulting from spray distillation, that 'is to say from a process in which the liquid to be distilled, such as hydrocarbon oil, is introduced in the vform of a fine spray into a current of hot steam or other inert gas, Vwhereby portions ofthe liquid are vaporized and are 'carried ofi' with such inert 'gas andare subsequently condensed therefrom. In this type of distillation as well as in vthetype-of steam distillation described above in which steam in blown or forced through a bod of heated oil or other liquid, the action ofY the stream of hot inert gas has a strong tendency to entrain ne particles of unvaporized liquid in the form of a mist and the feature of my invention which relates to the precipitation of mechanically entrained particles of unvaporized liquid priorto condensation is of great advantage in this connection. Furtheruiore the presence of inert gases causes a much greater volume iiow through the condenser than would be the case if no gas other than the vapors to be condensed were present and Consequently increases the tendency to entrain condensate in the form of mist from one stage tothe next and I therefore .nd it of great advantage in connection withsuch type of distillation to employ electrica precipitation to ensure removal within or immediately following each stage of anycondcnsate formed as a mist within such stage.

The distillation of hydrocarbon oils has been referred to above as a particular exam- .ple of the application of my process but it should he understood that it is applicable to the distillation of any lliquid containing constituents of dierent volatilities, and is of especial advantage in connection 'with the rectifying condensation of the vapors resulting from any such distillation process, with a view to obtaining the highest degreeV of separation between such constituents of different volatilities. It may be a plied for 4 example in connection with the istillation or first few stages of of benzol,` tar, or of various organic oils. esters, alcohols, etc. Itl may also be applied in connection with the recovery of'condensible constituents of varying volatilities in gas.

manufacturing processes or inv carbonizing coal retorts, and to the recovery of condensible constituents produced in oil shale distillation.

It will be understood that my improved method of distillation and condensation, as applied in any of the above described manners or for any of the above urposes, may bc carried out under any suitable conditions of pressure(y or vacuum, either during distillation, or during condensation or both.

What I claim:

l. An apparatus for separating 'constituents of different volatilities from vapors containing the same comprising, a condenser `rovided with successively arranged means or cooling vapor passing stages and with means for separatelycollect ing liquids condensed due to such successive cooling stages and for maintaining in the condenser a body of liquid socollectedin each stage so as to cause said liquidto be heated by the vapors therein, means for introducing vapors to said condenser, 'and means -for subjecting vapors passing through such,

condenser to electrical precipitating operations at portions thereof adjacent the respective cooling means to se arate therefrom suspended particles of condensed material.

2. An apparatus for condensation of vatherethrough in pors of varying volatilities comprising a g rectifying column provided with means for directing vaporsv upwardly therethrough, means Adefining a plurality of vertically superposed condensing chambers in said column through which such vapors are caused to pass successively, means for coolingrthe vapors in successive condensing chambers to successively lower temperatures, means in said column for separately collecting the condensate formed in each condensing chamber and maintaining a body of each' such condensate in the column so as to be heated by the vapors therein, and means for maintaining of a high potential electrical discharge directed through the' vapors toward said cooling means in each condensing cham- .v

ber.

3. An apparatus for separating constituents of different volatility from vapors, comprising a casing, means for introducing vapors to be treated at one end of saidcasing, a series of bandes projecting inwardly from the wall of said casing, another series of baffles within said casine and insulated .therefrom, said two series ofaflles being disposed alternately so as to cause said vapors. to follow a tortuous path through said casing, said rst-namedbales and the wall of said casing constituting cooling surfaces, and said other -*series lof baes yloe/nig rovided with discharge-electrode means 'ja a'pted to proi masiva duce electric discharge directed toward said cooling surfaces, and means for removing liquid collecting upon said rst-named baes.

4.' An apparatus for separating constituents of dierent Volatility from Vaporgcornprising a; casing, means for introducing vapors to 1loe treated at one end of said casing, a series of loai'es projectingrinwardly from the Wall of said casing and having means for holding collected liquid therefrom, the Wali of said casing and the under sides of said baies constituting cooling surfaces, means scribed my name this 13th day of Judy., 1925.' u

for removing collected liquid vfrom said bailles, lmeans within said casing having members so formed as to cooperate with said ballles to cause the vapors to follow a tortuous path through saidfcasinfg and to repeatedly* hringfsuch vapors in Contact with said cooling surfaces,.and means for causing electric discharge from said means In testimony whereof have hereunto suh- HARRY V. WELCH, 

